The tomato/potato psyllid from North America was first found in New Zealand in 2006, and is still spreading throughout the country.
It has now made its way south of Christchurch.
The psyllid can transmit a bacterium, Liberibacter, that is believed to cause the disease psyllid yellows in tomatoes and potatoes, and to cause zebra chip in cooked potato tubers.
These diseases can drastically reduce the quality and yield of infected crops.
Plant and Food Research has produced a leaflet to help home gardeners recognise the pest and its associated diseases, including guidance on control methods.
There are several kinds of psyllid found in home gardens in New Zealand, says entomologist Peter Workman of Plant and Food Research, but only this newly arrived tomato/potato psyllid is known to carry the Liberibacter bacterium.
Tomato/potato psyllid can be a problem for home gardeners, because it breeds on a range of garden crops from the Solonaceae and Convulvulaceae families.
Aside from tomatoes and potatoes, this psyllid can also be found on capsicums, chillis, egg plant and tamarillos, as well as on kumara, Apple of Peru and poroporo.
Gardeners should be vigilant and treat any plants that have been infested with psyllids as quickly as possible to reduce the risk of spreading disease.
An information leaflet about the tomato/potato psyllid, including how to spot it, what damage it can cause to garden crops and how to manage it, is available at www.insectwatch.com.
